一株好氧反硝化菌的筛选鉴定与特性研究

Screening and characterization study on an aerobic denitrifying bacteria

为筛选高效好氧反硝化菌,研究其适宜生长条件及好氧条件下反硝化性能,最终为该菌应用于水源水生物脱氮提供理论依据,采用平板划线、形态学观察、生理生化和16S r DNA序列分析筛选鉴定好氧反硝化菌的种属地位,考察了不同氮源、碳源、p H值、温度培养下菌株的生长状况以及该菌株的反硝化性能。筛选到的高效反硝化菌QX1经鉴定为节杆菌(Arthrobacter sp.),该菌在气浴摇床转速160 r/min条件下的适宜生长条件为:LB培养基+质量体积比为1%的乙酸钠,最适温度为30℃,最适p H值为8;菌株耐碱,可耐受15℃低温和40℃高温;生长曲线显示,在适宜条件下培养4 h后菌株生长进入指数期,此期维持约16 h,稳定生长24 h后进入衰亡期;菌株在合成污水中好氧培养48 h后,硝氮去除率可达到89.92%。菌株QX1可作为耐碱、温度耐受性广的高效好氧反硝化备选菌,在脱氮修复中具有良好的应用潜力,开发应用于低温或高温地区的水质改良将具有广阔的前景。

For screening efficient aerobic denitrifying bacteria, it is studied the suitable growth conditions and the performance of aerobic denitrification, and it is finally provided the theory basis for the biological denitrifi-cation about application of the bacteria in the water, using flat line, morphology observation, physiological and biochemical and 16S rDNA sequence analysis screening to denitrify the genus status of bacteria and examine denitrification performance of the strain under the growth condition of the different nitrogen source, carbon source, pH, temperature, cultivation strains. Efficient denitrifying bacteria QX1 section identified as Ar- throbacter sp. . The bacteria under the gas bath shaking table speed 160 r/min is that LB medium ＋ quality volume ratio of 1 % acetic acid sodium, the optimal temperature 30 °C , the optimum pH value 8 , strains of al-kali ,temperature 15 °C at low temperature tolerance and 40 °C at high temperature tolerance. The growthcurve showed that under the condition of suitable cultivation, strains grew into the index after 4 h period, thisperiod maintained about 16 h, strains entered the decline phase after 24 h stable growth, and strains in the synthetic wastewater aerobic training after 48 h, nitrate nitrogen removal rate could reach 89. 92% . The bacte-ria QXI could be used as alkali resistance, well low temperature resistance and high temperature resistance ofefficient denitrification alternative strains, developing low or high temperature area water quality improverwould have broad application prospects.